Although the quantity of detritus entering water-filled containers has well-known positive effects on performance mosquitoes such as Ochlerotatus triseriatus (vector of LaCrosse encephalitis) and Aedes albopictus (vector of dengue and other viruses), the mechanistic connection between detritus and mosquito production is less well understood. Most container mosquitoes do not feed detritus itself (leaves, insect carcasses, and nutrient-bearing stem flow), but rather on bacteria, fungi, and protozoans that form a food chain with detritus at its base. The few studies that have investigated the relationship between microorganism populations and detritus amounts or types have done so by measuring static densities of microbes, but such counts do not represent rates of productivity. It is the rate of conversion of these detritus resources to edible microorganism biomass that determines production of mosquito adults, and perhaps the composition of local container mosquito communities. We will determine how changes in the types and amounts of detritus inputs into containers affect the productivity (measured as rates of consumption of oxygen and leucine incorporation into protein) of microorganism communities, and how microorganism productivity translates into the performance Oc. triseriatus and Ae. albopictus, as well as the invertebrate community with which they exist. Our first specific aim is to determine how detritus input rates vary between tree holes (primary habitat of Oc. triseriatus) and tires (primary habitat of Ae. albopictus), and how these rates of input vary in space and time. We will use this information to pursue our second aim, determining how input rates are correlated with microorganism productivity in the field, and our third aim, determining how composition of detritus input determines microorganism productivity under controlled conditions. Our fourth aim is to determine how detritus composition, and associated differences in microorganism productivity affect the outcome of competition between Oc. triseriatus and Ae. atbopictus. Our fifth aim is to use information from aims 1 - 3 as a base for a field experiment to determine how changing total amount and rate of input of detritus to containers affects abundance of mosquitoes and invertebrate diversity in nature. This research will increase our knowledge of determinants of vector mosquito production and distribution and abundance.